Anatomy and Physiology 1 Midterm 1

Anatomy

study of the structure of the body parts

Physiology

Study of the function of body parts

Principle of complementarity of structure and function

Function relies on structural characteristic, the specificity of a structure will guide its function

Levels of Organization

Chemical → Cellular→ Tissue → Organ→ organ system→ Organismal

Organ Systems

Integumentary, Muscular, Skeletal, Urinary, Respiratory, Nervous, Cardiovascular, Endocrine, Lymphatic, Digestive, Reproductive

Maintenance of Life

Responsiveness, Adaptability, Growth and Development, Reproduction, Movement and Locomotion, Maintaining Boundaries, Respiration, Circulation, Digestion, Excretion

Responsiveness

organism recognizes changes in environment

Adaptability

ability to change organisms behaviour, capability or structure

Growth and Development

inherited patterns of growth and development (DNA) produce organisms characteristic of their speices

Reproduction

Produces the next generation

Movement and Locomotion

Distributes materials throughout large organisms, changes of orientation, position or movement

Maintaining Boundaries

Internal and External environments must be separated

Respiration

oxygen absorption and utilization (energy), carbon dioxide generation and release (waste)

Circulation

Movement of fluid within the organism; pump and network of vessels, may vary with size of organism

Digestion

the chemical breakdown of complex materials for absorption and use, may vary with size of organism

Excretion

elimination of chemical waste products created by organism, may vary with size of organism

Metabolism

the combination of anabolic and catabolic reactions

Catabolic reactions

break things down and release energy

Anabolic reactions

build larger molecules from smaller and consume energy

Survival Needs

Nutrients, Oxygen, Water, Normal Body Temperature, appropriate atmospheric pressure.

Homeostasis

maintenance of stable internal conditions, creating equilibrium

Homeostatic Control

Stimulus→ Sensor→ Control→ Effector

Sensor

monitors and responds to changes in environmental factors (stimuli)

Control Center

receives input from sensor, and guides response

Effector

receives output from control center , provides instructions for response

Negative Feedback

Reduce or stop stimulus

Positive Feedback

Response increases original stimulus, making variable even further from the norm

Language of Anatomy

Anatomical Position

Standing, feet apart, both palms facing forward with thumbs pointing laterally

Regional Term

specific terms allow to have more precise description of various body regions

Directional Terms

localization of one structure compared to another structure

Body Planes

Sagittal plane

splits body into left and right

Midsagittal section

placed on bodies midline

Parasagittal section

off centered (parallel)

Body Cavities

separated by membranes and sheaths, they enclose organs providing protection while accommodating changes in size and shape

Dorsal Cavity

encloses the cranial and spinal/vertebral cavity in a continuous manner

Cranial Cavity

enclose the brain

Spinal/ Vertebral Cavity

Surrounds spinal cord

Ventral Cavity

enclose the internal organs, two subdivisions separated by the diaphragm: thoracic and abdominopelvic cavity

Thoracic Cavity

Contains two pleural cavities, mediastinum containing pericardial cavity, and pericardial cavity

Pleural Cavities

two cavities each surrounding one lung

Mediastinum

Surrounds pericardial cavity, esophagus, trachea, etc.

Pericardial Cavity

Encloses the heart

Abdominopelvic Cavity

contains abdominal and pelvic cavity

Abdominal cavity

contains stomach, intestine, spleen and liver

Pelvic Cavity

contains urinary bladder, reproductive organs and rectum

Abdominopelvic regions

abdominopelvic quadrants

Serous membranes

thin double layered membranes that cover surfaces in ventral body cavity, double layer membranes separated by slit like cavity filled with serous fluid secreted by both layer, reduce friction between organs

Parietal Serosa

lines internal body cavity walls

Visceral serosa

covers internal organs

Pericardium

covers heart

Pleurae

surrounds lungs

Other body cavities

oral, digestive, nasal, orbital, middle ear, and synovial (joint (not exposed to environment)

Chapter 4

Tissue Layers

Tissue

similar cell types of structure and function that are grouped together

Histology

microscopic study of tissues

Epithelial Tissue

sheets of cells that cover external surfaces or cavities, that can also form glands

Connective Tissue

binds cells and organs together, provides support and protection

Muscle Tissue

excitable tissue that can contract, and allows for movement

Nervous Tissue

excitable tissue that generates and propagates signals to different parts of the body

Ectoderm

outer germ layer, that creates the epidermis, glands on skin, some cranial bones, pituitary and adrenal medulla, the nervous system, the mouth between cheek and gums, and the anus

Mesoderm

middle germ layer that creates connective tissue proper, bone, cartilage, blood, muscle membranes, serous membranes, kidneys and lining of gonads

Endoderm

inner germ layer, that creates lining of airways and digestive system except the mouth and distal part of the digestive system (rectum and anal canal), glands (digestive, endocrine and adrenal cortex

Epithelial Tissue (Epithelium)

consists of sheets of many cells covering body surfaces with little material (ECM) between and cavities also form glandular tissue, has two surfaces that differ in structure and function.

Avascular but innervates, obtains nutrients via diffusion through connective tissue

Main Functions: Protection, absorption, filtration, excretion, secretion, and sensory reception

Covering and lining epithelia

epithelium on external and internal surfaces Ex. skin endothelium of serous membranes

Glandular Epithelia

secretory tissue in glands Ex. salivary glands

distinguishing characteristics of epithelium

Polarity, cell to cell junctions, connective tissue support, avascular but innervated, high regenerative capacity

innervated

supplying of nerves

vascular

consisting of blood vessels

Polarity

movement and connection between cells and growth within direction

cell to cell junctions

specialized contact points bind adjacent epithelial cells together and allow communication between cells

Apical Surface

exposed to surface or cavity, smooth but may have projections or microvilli ( Top Layer)

Basal Surface

close to the underlying structure, attaches to basal lamina

Basal lamina

an adhesive sheet made of glycoprotein and collagen that secures to the reticular lamina and the underlying connective tissue

Tight Junction

specialized contact points that bind adjacent cells together

Gap junction

allow communication between cells

Desmosome

specialized contact points that bind adjacent cells together

Basement Membrane

junction between connective and epithelial tissue includes basal lamina and reticular lamina, reinforces epithelia, resists stretching and tearing, defines epithelia boundaries

Reticular lamina

network of collagen fibers

Regeneration of Epithelia

regenerates quickly, prompted by loss of polarity or lateral contacts, they are prone to damage as they line up external membranes

Simple Squamous Epithelia

single layer flattened scale like tissue foe the allowance of diffusion, and filtration, secretes lubricating substances. Can be found in air sacs of lungs, blood vessels, and lymphatic vessels

Endothelium

lining of lymphatic and blood vessels, heart

Mesothelium

serous membranes in the ventral body cavity

Simple Cuboidal Epithelia

single layer cubed box like tissue for absorption and secretion, in ducts secretory portions of small glands and in kidney tubules

Simple Columnar Epithelia

single layer tall column like tissue for absorption, and secretion of mucous and enzymes, Ciliated (bumpy) tissues are found in bronchi, uterine tubes, and uterus, non-ciliated (smooth) are found in digestive tract and bladder

Stratified Squamous Epithelia

2 or more layers of scale like flattened tissue for protection against abrasion, lines the esophagus, mouth, ad vagina

Stratified Cuboidal Epithelia

2 or more layer of box like cubed tissue for protection, quite rare, found in sweat glands, salivary glands, and mammary glands

Stratified Columnar Epithelia

2 or more layers of column like tall tissue for protection and secretion, found in male urethra and the ducts of some glands

Pseudostratified epithelium

single layer of ciliated irregular columnar epithelium secretes and moves mucus, lines the trachea, and most of the upper raspatory tract

Transitional Epithelium

allows the urinary organs to expand and stretch, lines the bladder, urethra and the ureters

Gland

cells that produces and discharges an aqueous fluid called secretion

Endocrine Gland

“Inside” multicellular ductless gland that secretes internally by exocytosis to interstitial fluid then into blood Ex. Horomones

Exocrine Gland

“Outside” unicellular or multicellular gland that secretes products onto body surfaces through a duct

Unicellular exocrine glands

mucous cells and goblet cells in the epithelial linings of intestinal and respiratory tract, produce glycoprotein (mucin) which acts as a lubricant and pathogen defence when dissolved in water (mucus)

Multicellular exocrine glands

composed of a duct and secretory unit, supported by connective tissue

Types of exocrine glands

Structure: simple vs. compound

Ducts: tubular vs. alveolar, tubuloalveolar

modes of secretion

Merocrine, apocrine, and holocrine

Merocrine Secretion

Exocytosis of secretion (Eccrine sweat glands)